This invention relates generally to agricultural chemicals. More particularly, the present invention relates to a closed agricultural chemical mixing system whereby highly toxic, concentrated pesticides, herbicides and the like may be properly prepared and loaded for subsequent spraying upon a desired field or crop.
In recent years it has become increasingly apparent that the variety of pesticides, herbicides and the like used in farming operations can be exceedingly harmful to both the environment and the personnel working at a job site. For example, the loading areas associated with aeronautical agricultural spraying operations tend to be repeatedly subjected to the vapors and residue associated with the various agri-chemicals which must be continuously loaded into the airplanes. In the past it has been the practice to simply pour the desired chemical concentrate manually into a tub or container, whereupon water may be haphazardly mixed until the desired chemical solution is achieved. "Systems" of the latter type, although characteristic of the prior art, are now in general disfavor because of the resultant deleterious environmental impact.
Closed agricultural mixing or batching systems employ a partial vacuum delivered to a holding tank of some form, which vacuum is then utilized to draw or suck the toxic contents of a container of herbicide or pesticide, etc. into the holding tank for subsequent mixing or diluting. After mixing in holding tanks the substance may then be forced into awaiting airplanes for spraying in the normal manner. The most representative prior art patent known to applicant in U.S. Pat. No. 3,976,087, issued to J. Bolton for a closed mixing system. Other patents of possible relevance are U.S. Pat. No. 3,797,744 which includes a plurality of chemical holding tanks and U.S. Pat. No. 3,640,319.
In a busy aeronautical agricultural spraying operation empty airplanes may continuously be approaching the service area for refilling. Where the airplanes must wait for the attendant to first mix the various holding tanks with the desired chemical and then unload the chemical, such sequential operation will result in an appreciable waste of time. It has been found most advantageous to provide a closed mixing system which is capable of loading one airplane while simultaneously mixing chemicals in anticipation of the arrival of the next airplane.
Therefore it is an object of this invention to provide a "closed system" agri-chemical mixing and transferring apparatus capable of simultaneously loading an airplane while mixing chemicals to prepare for another airplane.
A related object is to provide a closed mixing system of the character described which is environmentally sound and minimizes pollution.
A similar object of this invention is to provide a closed mixing system which minimizes the risk of exposure of the ground operator to the concentrated chemical preparations with which he must work.
Still another object of this invention is to provide a closed agri-chemical mixing system of the character described which is capable of self-cleaning its various constituent parts through a self-contained rinsing subsystem.
A still further object of this invention is to provide a closed system agri-chemical mixing system which may be completly self-contained and self-operable without the need for an external vacuum generation system.
Yet another object of this invention is to provide a closed agri-chemical mixing system which presents minimal danger to the ground personnel at aero-spraying facilities.
These and other objects and advantages of this invention, along with features of novelty appurtenant thereto, will appear or become apparent in the course of the following description.